JP3481787B2 - Electric car control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle control device for controlling an electric motor for driving an electric vehicle.

[0002]

2. Description of the Related Art As a control device for an electric motor for driving an electric vehicle, a plurality of AC electric motors are provided for one electric vehicle, and each of these AC electric motors has a corresponding variable voltage variable frequency inverter (hereinafter referred to as VVVF inverter). ) Some devices are controlled by a device.

By the way, in such a conventional electric vehicle control device, in order to grasp the electric motor rotation frequency and the basic electric motor current command used for controlling the VVVF inverter device, for example, a circuit configuration as shown in FIG. 10 is adopted. There is.

In FIG. 10, the electric motor rotation frequencies 2A to 2D obtained from the electric motor rotation speed sensor are the self-axis rotation frequencies 3A to 3D of the respective shafts. Further, the basic electric motor commands 7A to 7D are multiplied by the coefficient obtained through the switch 11 by the multipliers 9A to 9D and the multiplied values become the current patterns 8A to 8D, respectively.

In this case, the coefficient obtained from the switch 11 is switched by the high acceleration command 6, and the high acceleration command 6 is "1".
Then, the current is increased by, for example, increasing the coefficient by 1.3.

FIG. 9 is a schematic diagram showing the axle number and traveling direction of an electric vehicle. 1-No. The motor rotation frequency of each axis of No. 4 is detected and used as the control own axis rotation frequency of the VVVF inverter that controls the motor that drives each axis.

In the estimation of the vehicle speed in the electric vehicle system in which the electric motors are individually controlled, the average vehicle speed is calculated from the speed of the driving wheel shaft having the electric motor control, and the speed is used as the vehicle reference speed.

[0008]

However, the idling phenomenon between the wheel and the track caused by rain or snow causes a rapid change in the speed of the electric motor, which in turn changes the vehicle speed calculated from this speed. In particular, when all the axles rotate at the same time, the speeds of all the axles increase at the same time, and the true vehicle speed tends to be lost.

Therefore, the idle speed readhesion control for controlling the torque by comparing the vehicle speed with the speed of the own shaft is not properly performed,
There is a problem that the vehicle running performance is deteriorated. As described above, in the conventional electric vehicle control device, the vehicle speed is calculated from the speed of the driving wheel shaft having the electric motor control under any condition, and the calculated vehicle speed is used as the vehicle reference speed. It is difficult to obtain the optimum vehicle speed because the speed from the driving wheel shaft having the electric motor control is affected by the idling generated by the electric motor control under the environment where the electric motor control occurs.

The present invention has been made in order to solve the above problems, and it is an object of the present invention to reliably recognize a vehicle reference speed and perform fine torque control even under bad track conditions such as heavy rain. For the purpose of 1, and even in an environment where the idling phenomenon occurs continuously, predict the expansion of vehicle speed error caused by all-axis idling or idling, and optimize the idling adhesion control performance under optimal vehicle speed conditions. A second object of the present invention is to provide a control device for an electric vehicle.

[0011]

In order to achieve the above object, the present invention constitutes a control device for an electric vehicle by the following means. The invention corresponding to claim 1 is a control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, and selects and selects front two axes or rear two axes in the electric vehicle. One of the selected axles is selected as the reference speed target axis according to the traveling direction of the electric vehicle, and the rotation frequency signal of the motor or axle of the reference speed target axis is controlled by other motors or axles in the same electric vehicle. Is input to the inverter control circuit as the reference speed of the torque control.

According to a second aspect of the present invention, in a control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, one of the axles in the electric vehicle is set as a reference speed target. A shaft is selected, and the rotation frequency signal of the motor or axle of this reference speed target axis is input to the inverter control circuit as the reference speed for control of other motors or axles in the same electric vehicle, and it corresponds to the reference speed target axis. The inverter control circuit of the electric motor performs the torque control by reducing the electric current value of the electric motor with respect to the electric current values of the other shafts.

According to a third aspect of the invention, in the invention according to the second aspect, the reduction rate of the electric motor current value is changed according to the speed of the electric motor or the axle corresponding to the reference speed target shaft.

According to a fourth aspect of the invention, in the invention according to the second aspect, the setting target of the reference speed target shaft is switched according to the traveling direction of the electric vehicle. Therefore, according to the control device for an electric vehicle of the invention according to any one of claims 1 to 4, the electric motor for one of the axles in the same electric vehicle or the rotation frequency signal of the axle is used as the vehicle reference speed in the same electric vehicle. By inputting the torque to the inverter control circuit corresponding to the motor of the other shaft, the rotation speed of the main motor shaft will always be aware of the subtle difference in rotation speed from the rotation speed corresponding to the vehicle speed. Control can be performed.

According to a fifth aspect of the present invention, in a control device for an electric vehicle that individually controls a plurality of electric motors by means of corresponding variable voltage variable frequency inverter devices, one of the axles in the electric vehicle is idling controlled. It is selected as the reference speed target axis by monitoring, the rotation frequency signal of the motor or axle of this reference speed target axis is input to the inverter control circuit as the reference speed for control of other motors or axles in the same electric vehicle, and the reference speed The inverter control circuit of the electric motor corresponding to the target shaft reduces the electric motor current to the exciting current value regardless of the speed of the electric motor or axle corresponding to the reference speed target shaft, and at the value reduced with respect to the electric motor current of other shafts. Performs torque control.

According to a sixth aspect of the present invention, in a control device for an electric vehicle that individually controls a plurality of electric motors by means of corresponding variable voltage variable frequency inverter devices, one of the axles in the electric vehicle is idling controlled. It is selected as the reference speed target axis by monitoring, the rotation frequency signal of the motor or axle of this reference speed target axis is input to the inverter control circuit as the reference speed for control of other motors or axles in the same electric vehicle, and the reference speed The inverter control circuit of the electric motor corresponding to the target shaft stops the inverter control to open the electric motor.

According to a seventh aspect of the present invention, in a control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, one of the axles in the electric vehicle is in a slip control state. By selecting as the reference speed target axis by monitoring, the rotation frequency signal of the motor or axle of the reference speed target axis is input to the inverter control circuit as the reference speed for control of other motors or axles in the same electric vehicle, and the reference speed The target shaft is switched to a shaft that has a lighter shaft weight determined by the traveling direction of the electric vehicle.

Therefore, in the electric vehicle controller according to the inventions corresponding to the fifth and sixth aspects, for example, even when three electric motors idle at the same time, the speed of the open shaft is set to the vehicle reference speed. Therefore, idling can be detected, and divergence due to idling can be suppressed by idling readhesion control. Further, since the vehicle reference speed is not affected by the idling, the idling readhesion control can be appropriately performed based on the vehicle reference speed, and the torque reduction due to the idling can be minimized.

In the control device for an electric vehicle according to the sixth aspect of the present invention, the estimated vehicle speed value is not easily influenced by the idling which is caused by the variation in the adhesion due to the movement of the axle load which is likely to occur when the electric vehicle is accelerated. It is possible to reduce the error of.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a typical main circuit configuration example of an electric vehicle driven by a three-phase induction motor controlled by a VVVF inverter device as a first embodiment of the present invention.

As shown in FIG. 1, the DC power collected from the DC overhead wire via the pantograph 20 is connected in parallel through a high-speed circuit breaker 21 for inputting / outputting it and a unit switch 23 in which a charging resistor 22 is connected in parallel. 4 V
The VVVF inverter devices 24A to 24D are input, and the respective VVVF inverter devices 24A to 24D convert DC power into AC power of variable voltage variable frequency and supply it to three-phase induction motors (hereinafter simply referred to as motors) 25A to 25D. I am trying. In this case, the electric motors 25A to 25D correspond to No1 axis to No4 axis shown in FIG.

The rotation speeds of the electric motors 25A to 25D are respectively detected by rotation speed sensors 26A to 26D, and these rotation speed signals are output to the respective inverter control circuits 27A to 27.
Captured by D. Here, the rotation speed signals from the rotation speed sensors 26A and 26B of the electric motors corresponding to the No. 1 axis and the No. 2 axis are respectively the inverter control circuits 27 of their own.
In addition to A and 27B, they are input in parallel to inverter circuits corresponding to electric motors of other axes, and are used for control as reference speeds.

FIG. 2 shows a control block diagram for obtaining the self-axis rotation frequency during power running. In FIG.
The reference speed (FRS) is added to the conventional control block diagram shown in FIG. That is, as shown in FIG. 2, the motor rotation frequencies 2A to 2D become the self-axis rotation frequencies 3A to 3D of the respective shafts, and either the motor rotation frequency 2A or 2B is selected as the reference speed 5 through the switch 4. To be done. In this example, the switch 4 works by the vehicle traveling direction setting device (lever) 1 so that the motor rotation frequency 2A of the No. 1 axle is selected, for example, when a forward command is issued.

FIG. 3 is a control block diagram for generating a current pattern of the electric motor corresponding to each axis. In FIG. 3, the current reduction control for the motor current pattern of the reference speed target shaft is added to the conventional control block diagram shown in FIG. That is, as shown in FIG. 3, the speed-decrease coefficient pattern 12 created from the reference speed 5 obtained in FIG.
10B is switched to determine the target axis for current reduction.

When a forward command is issued from the vehicle direction travel setting device 1, the switch 10A turns on the speed-decrease coefficient pattern 1
2 is selected and multiplied by the motor current command 7A and the multiplier 9A to form a current pattern 8A, and the switch 10B selects a coefficient obtained through the switch 1 which is switched when the high acceleration command 6 is given to select the motor current command 7B. Is multiplied by the multiplier 9B to form a current pattern 8B.

As for the motor current commands 7C and 7D, the coefficient obtained by the multipliers 9C and 9D through the switch 11 and the multiplied value are the current patterns 8 as in the conventional case.
It becomes C and 8D.

In this case, when determining the current patterns 8A to 8D, the current patterns 8A to 8D are determined in consideration of the response load indicating the vehicle body mass. FIG. 4 is a block diagram of an inverter control circuit that torque-controls the three-phase induction motor of each axis using the self-axis rotation frequency and current pattern obtained from the control block diagrams of FIGS. 2 and 3 described above.

As shown in FIG. 4, the torque control circuit 33 is provided with an operation command 30 such as notch handling, and a current pattern 8 obtained from FIG. In addition, the differential speed monitoring control circuit 32
Is input with a reference speed 5 obtained from a rotation speed signal of an electric motor of an axle serving as a reference axis and a self-axis rotation frequency corresponding to each axis obtained from FIG. 2, and the idling state is detected by monitoring the difference speed. Then, the result is given to the torque control circuit 33. The torque control circuit 33 uses these operation commands 3
0, the current pattern 8, the torque control signal is output based on the monitoring result obtained from the differential speed monitoring control circuit 32 to VVV.
It controls the F inverter device.

Next, the operation of the thus configured electric vehicle controller will be described. First, in FIG. 2, from the motor rotation frequency 2A to 2D corresponding to each axis to the self-axis rotation frequency 3A.
3D is obtained, the difference between the electric motor rotation frequencies 2A and 2B is selected by the switch 4 which is switched by the vehicle traveling direction setting device 1 to be the reference speed 5, which is the self-axis rotation frequency 3A or 3B. In the example shown in FIG. 2, if the vehicle traveling direction setter 1 issues a forward command, the motor rotation frequency 2A of the No. 1 axle becomes the reference frequency.

Further, in FIG. 3, a current pattern 8 based on the variable load 31 from the motor current commands 7A to 7D for each axis.
In order to obtain A to 8D, the axis to be reduced is determined by the switches 10A and 10B that are switched by the vehicle traveling direction setting device 1, and the coefficient obtained from the speed-decrease coefficient pattern created from the speed reference described above is the motor current command. Current patterns 8A, 8A
It becomes B. In the example shown in FIG. 3, if the vehicle traveling direction setting device 1 is a forward command, the current pattern 8A of the motor of the No. 1 axle is obtained by multiplying the motor current command 7A by the coefficient obtained from the speed-decrease coefficient pattern. Become.

As described above, when the forward command is issued, the front side of the bogie No.
Fig. 2 shows that the current value is reduced with the axis of 1 as the reference axis.
Also, as shown in FIG. 3, the No. 1 shaft having a lighter axial load is used as a reference shaft and the No. 2 shaft having a heavy axial load is positioned as an original driving electric motor in order to set the overall knitting torque as high as possible. is there. Therefore, the reduction rate is such that the current value of the reference shaft motor does not run idle, for example, about 0.7 times the current value of the motor, as can be seen from FIG.

The self-rotational frequencies 3A to 3D and current patterns 8A to 8D of the electric motors of the respective shafts thus obtained are used for controlling the torque current in the respective inverter control circuits 27A to 27D shown in FIG.

In this case, the rotation speed signals of the No. 1 axis and No. 2 axis motors detected by the rotation speed sensor are not limited to the respective inverter control circuits 27A and 27B, but also to the other No. 3 axis and No. 4 axis inverter control circuits. Two
7C and 27D are also input in parallel and used as a speed reference.

That is, each inverter control circuit 27A-27
In D, the operation command 30 such as notch handling, the current pattern 8 corresponding to each axis obtained from FIG. 3 are given to the torque control circuit 33 as shown in FIG. Speed 5, in this example, the speed difference between the rotation speed signal of No. 1 axis and the rotation frequency of the own axis obtained from FIG. 2 is monitored, and when the idling state is detected, the result is given to the torque control circuit 33. VVV by the torque control signal output from the control circuit 33
The F inverter device is controlled.

As described above, according to this embodiment, since the reference speed can be accurately grasped, the torque control of each electric motor can be performed so that the rotation speed corresponding to the vehicle speed can be maintained with high accuracy. it can.

Further, although the motor torque itself, which is the reference speed axis, decreases, the other axis torque can be controlled so as to maintain a high adhesion ratio, so that the torque of the vehicle as a whole is at the same level or higher. Can be realized.

FIG. 5 shows V as the second embodiment of the present invention.
It is another example of the main circuit configuration of an electric vehicle driven by a three-phase induction motor controlled by a VVF inverter device.
In FIG. 5, the reference speed target axis is fixed to the No1 axis in advance with respect to the circuit configuration shown in FIG. In this case, the rotation speed signal of the No. 1 axis is input not only to its own inverter control circuit 27A but also to the other inverter control circuits 27B to 27D.

FIG. 6 shows the inverter control circuit 27 at this time.
It is a control block diagram for generating the electric current pattern of the electric motor corresponding to each axis used by A-27D. Figure 6
In Fig. 3, the reference speed target axis is previously set to No1.
The vehicle is fixed to the shaft, and the vehicle traveling direction setting device 1 and the switches 10A and 10B shown in FIG. 3 are omitted. In this case, the high acceleration command is applied only to motor currents (IC2 to IC4) other than No. 1 axis. Further, the coefficient according to the speed-decrease coefficient pattern 12 is also applied only to the electric motor corresponding to the No1 axis.

Even with such a configuration, the motor current corresponding to the No. 1 axis is reduced with respect to the motor currents corresponding to the other axes, and the current value is increased even when the current increase command is issued by the high acceleration command. Therefore, the torque can always be controlled in a state close to the rail-to-wheel adhesion limit.

FIG. 7 shows V as the third embodiment of the present invention.
1 is a system configuration showing a control device for driving a three-phase induction motor controlled by a VVF inverter device.
As shown in FIG. 7, the system according to the third embodiment includes a central control unit 40 that manages an individual electric motor system, individual inverter control devices 27A to 27D and electric motors 25A to 25D that control the electric motors, and the electric motors 25A to 25
D is individually controlled by the individual inverter control devices 27A to 27D.

FIG. 8 shows details of the central controller 40 and the individual inverter controller 27 of FIG. In FIG. 8, 41 is a current adding circuit into which electric motor currents corresponding to No. 1 axis to No. 4 axis of the electric vehicle shown in FIG. 9 are input, respectively.
42 is a motor current comparison circuit for comparing the added value of the motor current of each axis obtained by the current addition circuit 41 and the current command value Im *, and 43 is the output of the motor current comparison circuit 42 and the individual inverter control described later. An idling state determination circuit to which an idling detection signal output from the device is input, and 44 is an open axis selection circuit that selects an open axis based on the determination result of the idling state determination circuit 43 and outputs an opening command 45.

Further, 46 is an average speed calculation circuit to which the motor speeds Fr1 to Fr4 corresponding to the No1 axis to No4 axis of the electric vehicle are respectively inputted, and 47 is the motor speed Fr1 of each axis.
~ Fr4 and the output of the open axis selection circuit 44 are added respectively, 48 is the output of the average speed calculation circuit 46, the output of the open axis selection circuit 44 and the open axis switching circuit 4
7 is a reference speed switching circuit to which the outputs of 7 are added respectively.

These current adding circuit 41, motor current comparing circuit 42, idling state judging circuit 43, open shaft selecting circuit 4
4, the average speed calculation circuit 46, the open shaft switching circuit 47, and the reference speed switching circuit 48 constitute the central control unit 40.

On the other hand, the individual inverter control device 27 compares the output of the average speed calculation circuit 46 applied via the reference speed switching circuit 48 with the self-axis speed Fr to detect the idle rotation of the self-axis. When the idling detection circuit 49 detects the idling of its own axis, the idling readhesion control circuit 51 outputs a motor current reduction command 50.

Next, the operation of the control device for the electric vehicle thus configured will be described. In normal driving, the electric motor 2 shown in FIG.
5A to 25D are controlled by the individual inverter control devices 27A to 27D so as to operate at the same speed, and at this time, the motor current Im corresponding to No1 axis to No4 axis shown in FIG.
Since values 1 to Im4 are almost equal to the driver's cab current command value Im * from the current adding circuit 41, no large deviation is seen in the output value of the motor current comparing circuit 42.

At this time, the motor speeds Fr1 to Fr4 corresponding to the No. 1 axis to No. 4 axis have almost the same values, so that the output of the average speed calculation circuit 46 obtains a value that matches the speed of each motor.

This value is sent to each individual inverter control device 27 from the central control unit 40 which manages the individual electric motor control system with the vehicle speed as a reference, and each individual inverter control device 2
7 compares this speed with the self-axis speed Fr, and detects the idling detection circuit 4
The idle rotation of the own axis is detected by 9.

During normal running, the deviation between the vehicle reference speed obtained by the average speed calculation circuit 46 of the central control unit 40 and the self-axis speed Fr is small, so it is judged that the idling phenomenon has not occurred, and the idling readhesion control is performed. Is not done. In addition, since the electric motor current is not reduced by the idling readhesion control, the electric motor current is approximately the same as the cab command value Im *.

Next, in a situation where the wheels tend to idle due to rain or snowfall, the wheels tend to idle depending on the position of the wheel and the driving direction.
The motor speeds Fr1 to Fr4 corresponding to the axes No. 4 to No. 4 have different values.

In this case, since the speed of the shaft in which the idling occurs rapidly increases, the deviation from the vehicle reference speed becomes large, so the idling detection circuit 49 detects the occurrence of the idling and the idling readhesion control circuit 51. To output a motor current reduction command 50, and reduce the torque to re-adhere the wheels.

Further, under the environmental conditions in which idling occurs continuously, idling occurs at the same frequency on all axes, so idling readhesion control frequently works by idling detection, and the motor current is reduced by the motor reduction command 50. The cab current command value Im *
It becomes a low value for.

At this time, in the idling state determination circuit 43, the vehicle speed error caused by all-axis idling or idling is calculated from the current deviation obtained from the motor current comparison circuit 42 and the idling detection number per hour obtained from the idling detection circuit 49. The expansion of
The open axis selection circuit 44 selects an open axis according to the operating direction and the idling state, and outputs an open command to a specific individual inverter control device.

Here, when an opening command is issued from the central control unit 40 to a specific individual inverter control device 27, the individual inverter control device 27 controls the electric motor current command with an exciting current value obtained from the characteristics of the motor. Thus, control is performed with a sufficiently reduced torque, and as a result, the same condition as that when the electric motors are individually opened is set, and the speed of the shaft is used as the vehicle reference speed.

As another means, when an opening command is issued from the central control unit 40 to a specific individual inverter control device 27, control is performed by setting an axis that does not control the motor (inverter control stop). The condition is the same as when the motors are individually opened, and the speed of the shaft is used as the vehicle reference speed.

Further, as a means for controllably releasing the electric motor control, in consideration of a change in the load caused by the movement of the electric vehicle, a shaft for controllably opening the electric motor to a shaft having a lighter axial load determined by the traveling direction of the electric vehicle. The same conditions as when the electric motors are individually opened by switching to, and the speed of the shaft is used as the vehicle reference speed.

As described above, based on the release command issued to the specific individual inverter control device, the open shaft switching circuit 47 switches the speed to be the vehicle reference speed, and the reference speed switching circuit 48 calculates the average speed as the speed calculation method. The system is switched to the open axis calculation system, and this speed is sent to the individual inverter device 27 as the vehicle reference speed, and idling control is performed by each individual inverter control device.

As described above, in the third embodiment, even when, for example, three electric motors simultaneously idle, the speed of the open shaft is used as the vehicle reference speed, so that idling can be detected and the divergence due to idling can be prevented. It can be suppressed by idling readhesion control.

Further, since the vehicle reference speed is not affected by idling, proper idling readhesion control can be performed based on the vehicle reference speed, and the torque reduction due to idling can be minimized.

Further, it is difficult to be influenced by the idling which is caused by the variation of the adhesion due to the movement of the axle load which is likely to occur when the electric vehicle is accelerated, and the error of the vehicle speed estimated value can be reduced.

[0060]

As described above, according to the control device for an electric vehicle of the present invention, the main motor shaft rotational speed is controlled while always grasping a slight rotational speed difference from the rotational speed corresponding to the vehicle speed. Further, by using the same shaft in the vehicle as the main motor shaft as the reference shaft, the rotational speed deviation due to the shock absorber is small, and the torque control can always be performed in a state close to the adhesion limit between the rail and the wheel.

Therefore, since fine torque control can be performed, many advantages can be obtained in terms of wheel wear, riding comfort, economy as a vehicle system, and the like. In addition, even in an environment where idling occurs continuously, it is predicted from the control state that the vehicle speed error caused by idling on all axes or idling will increase.
Stable vehicle speed can be obtained by switching the vehicle speed,
It is possible to perform appropriate idling re-adhesion control at a vehicle speed that is not affected by idling, and it is possible to secure sufficient acceleration performance even under bad environmental conditions. Further, even when all the drive wheels are idle, the speed of the open shaft becomes the vehicle reference speed, so that the idle rotation is reliably detected and the torque reduction due to the occurrence of the idle rotation can be minimized.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing an example of a typical main circuit of a three-phase induction motor driven electric vehicle controlled by a VVVF inverter device according to a first embodiment of the present invention.

FIG. 2 is a control block diagram for obtaining a self-axis rotation frequency during power running in the same embodiment.

FIG. 3 is a control block diagram for generating a current pattern of an electric motor corresponding to each axis in the embodiment.

FIG. 4 is a block diagram of an inverter control circuit that torque-controls a three-phase induction motor of each axis in the same embodiment.

FIG. 5 is a system configuration diagram showing an example of a main circuit of an electric vehicle driven by a three-phase induction motor controlled by a VVVF inverter device as a second embodiment of the present invention.

FIG. 6 is a control block diagram for generating a current pattern of an electric motor corresponding to each axis in the embodiment.

FIG. 7 is a configuration diagram showing an electric vehicle system for individual electric motor control according to a third embodiment of the present invention.

FIG. 8 is a block diagram showing details of a central control unit and an individual inverter control device in the embodiment.

FIG. 9 is a schematic diagram showing an axle number and a traveling direction of an electric vehicle.

FIG. 10 is a control block diagram for generating a current frequency of an electric motor corresponding to a self-axis rotation frequency and each axis in a conventional electric vehicle control device.

[Explanation of symbols]

1 ... Vehicle traveling direction setting device, 5 ... reference speed, 6 ... high acceleration command, 7A-7D ... motor current command, 8A-8D
...... Current pattern, 9A to 9D ...... Multiplier, 10A, 1
0B, 11 ... Switch, 12 ... Speed-current reduction coefficient pattern, 20 ... Pantograph, 21 ... High speed circuit breaker, 22 ... Unit switch, 23 ... Charging resistance, 24A
-24D ... VVVF inverter device, 25A-25D
...... Electric motor, 26A to 26D ...... Rotation speed sensor, 2
7, 27A to 27D ... Inverter control circuit, 30 ...
Operation command, 31 ... Adaptive load, 32 ... Differential speed monitoring control circuit, 33 ... Torque control circuit, 40 ... Central control unit, 4
1 ... current adding circuit, 42 ... motor current comparing circuit, 4
3 ... idling state determination circuit, 44 ... open axis selection circuit, 4
5 ... Release command, 46 ... Average speed calculation circuit, 47 ...
Open axis switching circuit, 48 ... Standard speed switching circuit, 49 ...
Idling detection circuit, 50 ... Motor current reduction command, 51 ...
Spin-off readhesion control circuit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H02P 5/50 H02P 5/50 D (56) Reference JP-A-1-291604 (JP, A) JP-A-54-51110 ( JP, A) JP 61-227603 (JP, A) JP 61-157202 (JP, A) JP 63-262003 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60L 9/18 B60L 3/00 H02P 5/41 H02P 5/46 H02P 5/50

Claims (7)

(57) [Claims] 1. A control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, wherein front two shafts or rear two shafts in the electric car are selected, and each of the selected axles is selected. One of the shafts is selected as the reference speed target shaft according to the traveling direction of the electric vehicle, and the rotation frequency signal of the electric motor or axle of the reference speed target shaft is used as the reference speed for control of other electric motors or axles in the same electric car. A control device for an electric vehicle, characterized in that the control device inputs torque to an inverter control circuit. 2. In a control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, one of the axles in the electric vehicle is selected as a reference speed target shaft, and this reference is selected. Input the rotation frequency signal of the electric motor or axle of the speed target axis to the inverter control circuit as a reference speed for controlling other electric motors or axles in the same electric vehicle,
An inverter control circuit of an electric motor corresponding to the reference speed target axis performs torque control by reducing the electric current value of the electric motor with respect to electric current values of other axes. 3. The electric vehicle controller according to claim 2, wherein the reduction rate of the electric motor current value is variable according to the speed of the electric motor or the axle corresponding to the reference speed target shaft. Electric vehicle control device. 4. The control device for an electric vehicle according to claim 2, wherein the target object of the reference speed is switched depending on a traveling direction of the electric vehicle. 5. A control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, wherein one of the axles in the electric vehicle is used as a reference speed target axis by idling control state monitoring. The motor for the reference speed target shaft or the rotation frequency signal of the axle is input to the inverter control circuit as a reference speed for control of another motor or axle in the same electric vehicle, and the motor corresponding to the reference speed target shaft is selected. The inverter control circuit of (1) lowers the electric motor current to an exciting current value regardless of the speed of the electric motor or axle corresponding to the reference speed target shaft, and performs torque control with a reduced value with respect to the electric motor current of other shafts. An electric vehicle control device characterized by: 6. A control device for an electric vehicle that individually controls a plurality of electric motors by a corresponding variable voltage variable frequency inverter device, wherein one of the axles in the electric vehicle is set as a reference speed target axis by idling control state monitoring. The motor for the reference speed target shaft or the rotation frequency signal of the axle is input to the inverter control circuit as a reference speed for control of another motor or axle in the same electric vehicle, and the motor corresponding to the reference speed target shaft is selected. The control device for an electric vehicle is characterized in that the inverter control circuit of (3) stops inverter control to open the electric motor. 7. A control device for an electric vehicle that individually controls a plurality of electric motors by corresponding variable voltage variable frequency inverter devices, wherein one of the axles in the electric vehicle is set as a reference speed target axis by idling control state monitoring. The reference frequency target shaft electric motor or axle rotation frequency signal is input to an inverter control circuit as a reference speed for control of another electric motor or axle in the same electric vehicle, and the reference speed target shaft is the electric vehicle. The control device for the electric vehicle is characterized in that the shaft load is determined to be lighter depending on the traveling direction of the electric vehicle.